fix: EXPOSED-158 avoid SQL syntax error of CASE WHEN using nested CASE (

JetBrains#1847) * fix: EXPOSED-158 insert space before WHEN to avoid SQL syntax error ENDWHEN using nested CASE * fix: EXPOSED-158 insert space before WHEN added the test code and removed unnecessary code for this problem
naftalmm · Aug 30, 2023 · fe4c41a · fe4c41a
1 parent cb721fe
commit fe4c41a
Show file tree

Hide file tree

Showing 2 changed files with 29 additions and 3 deletions.
diff --git a/exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/Function.kt b/exposed-core/src/main/kotlin/org/jetbrains/exposed/sql/Function.kt
@@ -393,14 +393,14 @@ class CaseWhenElse<T, R : T>(
 
     override fun toQueryBuilder(queryBuilder: QueryBuilder) {
         queryBuilder {
-            append("CASE ")
+            append("CASE")
             if (caseWhen.value != null) {
-                +caseWhen.value
                 +" "
+                +caseWhen.value
             }
 
             for ((first, second) in caseWhen.cases) {
-                append("WHEN ", first, " THEN ", second)
+                append(" WHEN ", first, " THEN ", second)
             }
 
             append(" ELSE ", elseResult, " END")

diff --git a/exposed-tests/src/test/kotlin/org/jetbrains/exposed/sql/tests/shared/dml/ConditionsTests.kt b/exposed-tests/src/test/kotlin/org/jetbrains/exposed/sql/tests/shared/dml/ConditionsTests.kt
@@ -210,4 +210,30 @@ class ConditionsTests : DatabaseTestsBase() {
             }
         }
     }
+
+    @Test
+    fun testChainedAndNestedCaseWhenElseSyntax() {
+        withCitiesAndUsers { cities, _, _ ->
+            val nestedCondition = Case()
+                .When(Op.build { cities.id eq 1 }, intLiteral(1))
+                .Else(intLiteral(-1))
+            val chainedCondition = Case()
+                .When(Op.build { cities.name like "M%" }, intLiteral(0))
+                .When(Op.build { cities.name like "St. %" }, nestedCondition)
+                .When(Op.build { cities.name like "P%" }, intLiteral(2))
+                .Else(intLiteral(-1))
+
+            val results = cities.slice(cities.name, chainedCondition).selectAll()
+            results.forEach {
+                val cityName = it[cities.name]
+                val expectedNumber = when {
+                    cityName.startsWith("M") -> 0
+                    cityName.startsWith("St. ") -> 1
+                    cityName.startsWith("P") -> 2
+                    else -> -1
+                }
+                assertEquals(expectedNumber, it[chainedCondition])
+            }
+        }
+    }
 }